Alternating-current-controlling apparatus.



E. L. GALE, s3. 7 ALTEBNATINGUUBBENT CONTROLLING APPARATUS. LPPLIUATIOHFILED DEC. 18, 1905.

1,089,919. Patent ed Mar.10,1914.

Wit-"cow ,Curre'nt-Controlling Apparatus, of which a b 0, represent themains from the source alternating current electric motors with minimumconsumption of current and miniprising the lever O and the insulatedcontact UNITED STATES PAT more mss'r L. GALE, sa, orYoNKE'nJs, NEW

YORK, ASSIGNOR tro OTIS ELEVATOR comm, or JERSEY CITY, NEW senses, aconronerron or new chaser.

ALTERNATING-CURBENT-QQNTROLLING APPARATUS.

Specification of Letters Patent. Patented 11,13 if}? 4.,

Application filed December 18, 1905, Serial No. 292,121, 2 i

To all whom it may concern Be it known that I, ERNEST L. GALE, Sn, acitizen of the United States, residing at Yonkers, in the county of\Vestchester and State of New York, have invented a new and usefulImprovement in Alternatingthe following is a specification.

My invcntionrelates to means for starting alternating current motors,and one of its objects is the provision of simple, cheap and efficientmeans for starting and operating mum noise.

Another object of my invention is the provision for automaticallyprotecting an electric motor if the source'of supply is cut off andthereafter turned on again while the controlling switch. remains inclosed position.

Other objects of my invention will appear hereinafter, the novelcombinations of 'elements being pointed out in the claims.

Referring to the single figure of the drawing which illustratesdiagrammatically my improved system of circuits and apparatus,

of alternating current supply.

S designates a main line switch. C designates an elevator car in whichis placed the manual controlling switch com strips 0, (Z, 12, 59 and 1360.

P designates a potential switch or automatic main line switch.

I designates an induction motor, B an al ternating current"electro-magnetic brake therefor, and --R the reversing switch apparatusfor the motor circuits.

D designates the starting resistances for the motor with its operatingmeans connected thereto.

'When the switch lever O is moved to circuit-closing position, forinstance to the right, so as to connect contacts 12, 13, and d, a single'phase circuit will be closed from main a through one blade of thethree-pole switch S, and thence by wires land 11, contact 12, switchlever 0, contact 13, wire 14, resistance 15, wire 16, coil 17 of thepotentialswitch P, wire 18', to one of the other mains, as b, which maybe designated the common return. The resistance 15 is so constructedthat it will prevent suilicient current from passing through coil 17- tocause the latter to move its core 26 so as to effect the closure of theswitch 19, comprising contacts20, 21, 22 and 23. The contacts 20,23, arefixed, while the contacts21 and 22 are. movable, being mounted on'a bar25, of insulating material, which issecured to the upper end of the stem24;, which in turn isrigidly connected to core 26. When the switch leverO is moved to theright-hand position, as hereinbefore referred to, acircuit will also be closed from main a to wires 1 and 11, contact 12,switch lever 0, contact strip 0?, wire 27, C011 28 of the reversingswitch R, wire 29,

contacts 30, 31, wires 34., 35, 36 coil 3? of the operating means forthe motor-accelerating apparatus, wire 38,-wire 67 to terminal 10 of theinduction motor I, and thence through a part of its stator winding tomotor ter minal 9, and by way of common return'2 to the main 5-. Sincethe contacts 30and 31 are'in engagement at this time the resistance r isshort-circuited so that suliicient current will flow through coil 37 toenable it to draw up its core 39 and insert the starting resistances 49and 50 in the rotor circuits of the induction motor I. i

If the switch lever O is moved toits lefthand position so as to connectthe contact strips 59, and d, a circuit will be closed from the main 0through the switch S, and then by wires 3 and 58 to contact 59, switchlever 0, contact 60, from which the circuit continues by wire 14,through the resistance 15, Wire 16, coil'17, to the common return 2, andout through the switch S to main 6. As before the coil 17 cannot actuateits core- 26, by reason of the resistance 15 be-' ing in circuittherewith. A circuit is also closed by swit'ch leverO in its left-handpowires 3 and 58, contact .79, lever 0, contact strip (Z, and'thenc e bywire 1 to and through coil 62, resistance r, wire 36, coil 37, wire 38,main 7. motor terminal 10, part of the stator winding on induction motorI, motor terminal 9, to common return 2. It will be noticed that in thiscase the resistance 7 is in circuit both with the coil 62 and the coil37. Sufficient current is allowed to fiowthrough the coil or solenoid 62to enable it to actuate its core 64 to move its stem 63 to the left.This stem has a pin-and-slot connection 62', with a tilting oroscillating lever 32-, which is connected to a fixed pivot 33, andcarries a weight W at its upper end to hold the lever 32 in either oneor the other of its circuit-closing positions. The lower end of thislever 32 carries an insulated con tact 31, which is adapted to engagethe fixed contact 30 or the fixed contact 63. When in position shownthatis, when the contacts 30 and 31 are in engagement with each other, theresistance r is short-circuited through the wires 29, 34 and saidcontacts. lVhen the lever 32 is moved to its opposite position, however,by the energization of the coil 62, the resistance r will beshortcircuited. This has the effect. of increasing the amount of currentwhich can flow through the solenoid 37, to such an extent as to enablethe latter to move upwardly its core 39. Thus it will be noticedsolenoid 37 cannot operate until after the reversing switch hasabsolutely operated and responded to the position of car switch. Thecore or plunger 39 is connected to a piston of ,a dashpot, which isprovided with an air-cock 45, and an outwardly opening valve 44 on itsupper side. The valve 44 allows the piston to ascend quickly, but closesautomatically when the piston descends. But the aircock 45 is adjustedto allow the air to enter said dash-pot slowly, so that the core 39,with the bridge piece 46, may slowly descend when desired. WVhen thesolenoid 37 is energized sufficiently to lift its plunger 39, andconsequently the bridge piece 46 with a rapid motion, the resistances 49and 50 are quickly inserted in the rotor circuits of the inductionmotor 1. Furthermore, when the plunger 39 reaches the upper limit of itstravel it strikes against lever 40, which is pivoted at 41, and normallyrests on a fixed stop 42 to maintain the switch 43 in open position.lVhcn, however, the 1ever,40 is moved upwardly the switch 43 is closedto short-circuit the resistance 15. This obviously decreases theresistance of the circuit through the solenoid 17 of the potentialswitch P and said solenoid now receives suflicient current to enable itto lift its core or plunger 26 so as to close the switch 19. Thus itwill be noticed all three magnets are absolute in action.

The'motor brake B will now be energized as a circuit is closed from maina through switch S, wire 1, contacts 20 21, wire 4, wire 57, through thecoils of said brake magnet, and thence to the common return 2. The brakeis preferably applied by means of a spring, and released by thealternating cur- .rent brake magnet B. The motor may now start, thecircuits therefor, being closed through the switch 19 and the reversingswitch R, the position of the latter determining in which direction themotor I shall rotate. If the manual operating switch lever 0 is in itsright-hand position then the reversing switch will assume the positionshown in the drawing, and the motor circuits may be traced as follows:from main a, through wire 1, contacts 20 21, wire 4, fixed contact 53,contact 54, which is carried by lever 32, but insulated therefrom, andthen by wire 7 to motor terminal 10; another circuit is completed frommain 0, through switch S, wire 3, contacts 23 and 22, wire 5, fixedcontact 51, contact 52, which is also carried by but insulated fromlever 32, wire 6, to motor terminal 8; and the thirdcircuit comprisesthe common return 2, which is permanently connected to the motorterminal 9.

When the switch lever O is moved to its left-hand position the lever 32is moved to its left-hand position, so that the contacts 52 54 carriedtherebywill engage respectively with fixed contacts 55 56 instead ofwith the fixed contacts 51 53. In either case after the reversing switchlever 32 has once been moved to one of its circuit-closing positions,the solenoids 62 or 28 need be depended upon vno longer for holding saidlever in circuit-closing position, as this is done by gravity-that is,the weight 1V acts to hold the reversing switch closed. lVhen thereversing switch lever 32 has been moved to its left hand position thecircuits for the motor are changed at the mains a, 0 and motor terminals8, 10. That is, two of the phases of themotor stator are reversed inthat main a is now connected by wire 4, contacts 55, 52, to mainterminal 8, while the I main 0 is connected by wire 5, contacts 56 54,and wire 7 to motor terminals 10. The direction of rotation of thelnduction motor I will therefore be reversed. The induction motor Ihaving thus been started in the de sired direction after the resistances49 and 50 are inserted 'in the rotor circuits, it will be noticed thatwhen the switch 19 is closed the reversing switch solenoids and thesolenoid 37 are short-cireuited. If the switch lever O is assumed to bein its righthand position and the switch 19 closed the short-circuit ofthe circuit starting at point 66 may be traced through the contacts 2021, wire 4, contacts 53, 54, and by wire 7 to the point 67, which isconnected by wire 38 to the coil 37. If the switch lever O is in itsleft-hand position, and consequently also the reversing switch levercontacts 52 and 54, and the switch 19 is in closed position theshort-circuit of the circuit, including the coils 62 and 37, may betraced from point 68 through contacts 23, 22, .wire 5, contacts 56 and54, and again by wire 7 to the point 67. It is therefore evident that assoon as either of the reversing switch magnets and the solenoid 37 havedone their work these magnets and'solenoid are shortcircuited. This hasthe effect of releasing. the core or plunger 39, and the bridge piece 46therefore gradually moves downwardly over the contacts 47, 48, againstthe action of the dash pot, and step by step cuts out the sectionalstarting resistances 4:9 and 50,

40 is also released, and therefore switch 43 isopened to re-insert theresistance in circuit with the solenoid 17, of the potential switch P.Although the current passingthrough the coil 17 when the resistance 15is in circuit therewith is not sufiicient to "cause said coil to liftits core 26, this ourrent is suflicient to hold said core 26 in itsuppermost position after it has once been placed in' such position. Thecontacts ,of

the switch 19 will therefore be held in engagement with each other withthe minimum consumption of current.

Although I have herein shown only oneform of my invention, obviouslythose skilled in the art may make changes and variations thereof withrespect to the details and the arrangement of parts without departingfrom the spirit and scope of my invention as defined by theclaims. Itherefore do not wish to be limited. to the exact construction hereindisclosed.

What I claim and desire to have protected by Letters Patent of theUnited States is 1. The combination with analternating current motor ofthe induction type; of a reversing switch therefor; electro-magneticmeans for operating said reversing switch; manual means for controllingsaid electric means; a sectional starting-resistance; electromagneticmeans for inserting said resistance in the rotor circuits;current-reducing resistance for preventing the operation of saidelectro-rnagnetic means; means co-acting with said reversing switch forshortcircuiting the said current-reducing resistance and effecting theinsertion of said starting resistance; an electro-magnetic main lineswitch; an additional resistance preventing the operation of said mainline switch: means co-acting with said electromagnetic means forinserting the starting resistance, to short-circuit said additionalresistance and'efi'ect .the operation of said main line switch; andcircuits and connec- "tions for effecting the cutting out of the elec'tric means for operating the reversing switch, and also the cutting outof theelec t re-magnetic means for inserting the starting-resistance toeffect the re-insertion of said additional resistance and also theautomatic. operation of said accelerating apparatus.

2. The combination with an alternating current motor, ofmeans forcontrolling the same comprising an electromagnetic switch for theprimary circuit. a variable impedance for the secondary, circuit, acontrolling element therefor havlng a bias toward a.

minimum impedance position, an electromagnetic device for moving saidelement to a maximum impedance position, and connections whereby thecircuit of the primary switch is closed when said element reaches thelatter position.

In a self-starter for electric motors, the combination with a rheostat,of an electromagnet for operating said rh'eost'at, a motorreversing'switch', resistance in circuit with said electromagnet; meanscontrolled by the position of said reversing switch for short- Icircuiting the resistance and thereby controlling said electro-magnet,and devices for operating said reversing switch.

4. In a self-starter for electric motors, the combination with arheostat, of reversing switch mechanism, a manual controllingSWitCll,*tlIl electro-magnet for operating said rheostat, resistance incircuit with said'electromagnet, and means operated by the reversingswitch to short circuit said resistance when the reversing switch is inposition corresponding to the position of said manual switch. 7' i 5. Inaself-starter for electric motors, the combination with a rheostat, ofan electromagnet-for operating the same, a motor reversing switch, aresistance in circuit with said electrdmagnet to prevent its operation,and a switch dependent upon the position of said reversing switch forshort-circuiting said resistance.

6. In a self-starter for electric motors, the combination with a'rheostat, of an electromagnet for operating the same, a motor re iceversing switch of the gravity type, electromagnets for shifting theposition of said reversing switch, resistances in series with said firstnamed electro-magnet, and a switch for controlling said resistances toef- 7. In a self-starter for electric motors, the" combination with anelectromagnetic rheostat, of reversing switches of the gravity type,means for preventing the operation of said electro-magnetic rheostatuntil said reversing switch is in a predetermined position, a mainline/switch, means for preventing the closure of said main line switchuntil said electro-magnetic rheostat is in starting position, andcircuitsfor short-circuiting the electro-magnet of said electro-magneticrheostat and also said reversing switch magnets.

8. In a self-starter for electric motors, the combination with a.rheostat, of an electromagnet for operating said rheostat,electromagnetic reversing switch mechanism, means dependent on saidreversing switch mechanism for controlling said rheostat electromagnet,an electro-magnetic main line switch, means dependent on said rheostatelectro-magnet for controlling the operation of said main line switch,and means operated by said main line switch for eliminating the currentin all the aforesaid electro-magnets except that of the main lineswitch.

9. In a self-starter for electric motors, the- 10. In'a self-starter forelectric motors,

the combination'with a rheostat, of an electro-magnet for operating thesame, a motor reversing switch, a pair of electro-magnets for operatingsaid reversing switch, said first and second named electromagnets beingconnected in series, means dependent upon the position of said reversingswitch for contro ling the operation of said firstnamed electromagnet, a'main line electro-v magnetic switch, means dependent upon said,rheostat electro-magnet for controlling said main line switch, and amanual switch for controlling said reversing switch magnets.

11. In a self starter'for electric motors, the combination" with arheostat, an electromagnet for operating the same, a motor reversingswitch of the gravity type, a pair'of electro-magnets for s ifting saidreversing switch from one position to-another, a pair of resistances incircuit with the rheostat electro-magnet to prevent its operation, a

manual switch for controlling the circuits of the aforesaidelectro-magnets, and switch ances to cause sufiicient current to flowthe reversing switch is in a position corresponding to the position ofsaid. manual switch. I

I v13. In a ,self-starter for electric motors, the combination with arheostat, of an elecs reversing switch, means for operating saidreversing switch, a resistance in circuit with .said electroa'nagnet toprevent its operation when the reve'rsing switch .is 'out of properposition, a main line switch, an elec-' tro-magnet for operating saidmain line switch, and circuits and connections for efswitch after therheostat has been set.

name to this specification in the presence of two subscribing witnesses.

ERNEST L. GALE, s3.

\Vitnesses CHARLES M. NISSEN,

ALFRED O. BEGHET.

Copies of thil patent may be obtained for five cents each, by addressingthe Gommlssioner of Patents Washington, D. O."

mechanism dependent upon said reversingswitch .to short-c1rcu1t one ofsaid resist-- through said rheostat electro-magnet to 0ptro-magnet foroperating the same, a motor fecting the operation of said main line I Intestimony whereof, I have signed my cause said rheostat magnet tooperate when

